How to reproject to other projections than WGS84 or Webmercator?

Question

I have an OpenLayers map with a vector layer to add points on. I'm using Google Maps as the base layer. After the point is added, I need to store the data in my database as lat/long and x/y. Can I transform the projection of the x/y points or convert the lat/long to x/y? The x/y that is on the point is in spherical mercator so it doesn't work for me.

Update: I'm not having any trouble converting the x/y to lat/long. I want to convert the x/y that I have to a different projection. I'm not sure that's the right terminology, but I need to convert the x/y values.

Update: The SRID I need is 3734. When I drop the point, the x/y is like: x: -9058948.6891836 y: 5035248.6338434

But what I need looks more like: x: 2282175.42 y: 545126.58

I'm also using PostGIS so if this is possible to do with PostGIS I'm open to that also.

Answer 1

As per your update, a PostGIS solution would work as well;

You need ST_Transform to project in the data Postgis from EPSG 3857 to EPSG 3734

SELECT ST_AsText( ST_Transform(
ST_GeomFromText('POINT(-9058948.6891836,5035248.6338434)',3857),3734)) As wgs_geom;

Answer 2

There's a library called proj4js can do this job, and you can use it together with OpenLayers. Have a look at OpenLayers Projection class.

Answer 3

Try to do more research before posting questions. I don't know openlayers, but I found the answer in googling your title "OpenLayers X/Y Projection" in 30 sec. See http://stackoverflow.com/questions/2601745/how-to-convert-vector-layer-coordinates-into-map-latitude-and-longitude-in-openl

var toProjection = new OpenLayers.Projection("EPSG:4326");
var fromProjection = new OpenLayers.Projection("EPSG:900913");
var convertedPoint = new OpenLayers.LonLat(x, y);
convertedPoint.transform(fromProjection, toProjection);